1. Field of the Invention
The present invention generally relates to portable spectroscopic imaging microscopes, including portable Raman imaging microscope systems and portable fluorescence imaging microscope systems.
2. Description of Prior Art
Conventional spectral microscope systems allow a sample to be viewed through a video camera or an eyepiece. However, the sample must generally be fixed on a movable stage or table of the microscope and moved toward or away from the objective lens to achieve proper focus as disclosed, for example, in U.S. Pat. Nos. 5,194,912; 5,442,438; 5,479,252; 6,002,476 and 6,069,690. For some applications, such as samples in a vacuum chamber, in an oven, or located in a manufacturing process, one cannot use such conventional spectral microscope systems. U.S. Pat. No. 6,008,894 discloses a Raman spectroscopy probe for analyzing specimens in adverse environments requiring remote focusing of the probe, and suggests mounting the probe to achieve nanometer positional variations. U.S. Pat. No. 6,115,528 discloses a fiber optic based probe assembly for use in hostile environments, but the probe heads do not allow the sample to be directly viewed and thus do not allow the collection of either a single or multiple spectra from precisely identified locations within a sample, as visually viewed through the same objective lens used to collect the spectra. One system that does allow the collection of either a single or multiple spectra from precisely identified locations within a sample, as visually viewed through the same objective lens used to collect the spectra is disclosed in my earlier U.S. Pat. No. 6,310,686, which does suggest manual and machine-powered manipulation of a probe head containing the objective lens, but required spacing from the sample by less than 1 cm and did not disclose any mechanism for accurately positioning the probe head.
Despite the variety of spectral microscopic systems that have been developed, there remains a need for a portable spectroscopic microscope system that is easily adapted to a variety of work environments and allows the simultaneous observation of the sample and acquisition of spectral information from the sample. There is a further need for a spectroscopic microscope system that can be used any angle and is sufficiently portable to be brought to a stationary sample rather than requiring that the sample be set on a translation stage for alignment to a fixed microscope objective. There is particularly a need for a portable spectroscopic microscope system having the forgoing mobility that requires no optical realignment upon movement of the system from one position to another.